Chapter 4 Mental Retardation

CHAPTER 4 MENTAL RETARDATION

1. AAMR (American Association on Mental Retardation) Definition Components A. Sub average intellectual function - lowering from 80 - 85 to 70 -75 IQ (5 point spread to emphasize lack of preciseness) Mild 50 - 75 Moderate 40 - 50 Severe 0 - 40 B. Limitations in Adaptive Behavior Infancy Preschool School age Adult C. On set of Mental Retardation during the developmental period - before age 18

2. Mental Retardation as improvable and possibly non- permanent (not incurable in mild range)

3. Beyond the AAMR definition, in 1992 the AAMR recommended that professionals classify individuals with MR according to "intensity of support needed".

4. Prevalence - Theoretical vs. Real IQ Distributions

1 A. Theoretical estimate = 2.27%

B. Current data only 1 - 1.5% identified as retarded - possible reasons

C. Most of MR students are mildly retarded with the least being severely retarded.

5. Causes of MR A. AAMR categories causes of MR by "the time at which the cause occurs" (1) Prenatal (before birth) (2) Perinatal (at the time of birth) (3) Postnatal (after birth)

B. Causes (1) Prenatal Example: Down Syndrome - chromosomal disorder - chromosomal accident - usually not an inherited condition - degree of retardation varies widely with Down Syndrome -Down Syndrome is the most common form of MR present at birth - the likelihood of having a child with Down Syndrome increases with age of the mother

2 Example: Hydrocephalus - Dev. Disorder of Brain Formation - accumulation of cerebral spinal fluid inside or outside of the brain - pressure on the brain and enlargement of the skull - degree of MR depends on how early condition is diagnosed and treated - treatment: surgically placed shunt that drains excess fluid away from the brain

Example: Fetal alcohol syndrome (FAS) - Environmental Hazard - expectant mothers consume large amounts of alcohol - physical deformities as well as MR - even moderate drinking during pregnancy can cause mild behavioral abnormalities -preventable with education

(2) Perinatal Example: Low Birth weight (LBW) - result from a variety of behavioral and medical problems - associated with poor nutrition, teenage pregnancy, drug abuse, excessive cigarette smoking - potentially preventable with medical care and education (3) Postnatal

3 Example: Cultural - familial MR - - mild retardation - due to an unstimulating environment and/or hereditary factors - cause of the vast majority of mild MR

Example – biological postnatal causes: traumatic brain injury (TBI), infections, malnutrition, and toxins

6. Assessment A. Intelligence Tests (1) I.Q. (Intelligence Quotient) MA – mental age CA – chronological age - IQ = MA/CA X 100 MA8/CA10 X 100 = .8X100=80 IQ a. a nine year old who functions like a 6 year old a. 6MA/9CA = 66.9 = 67 IQ b. 6MA/12CA = e. 12MA/9CA c. 9MA/6CA = f. 8MA/10CA d. 9MA/12CA =

(2) IQ scores in perspective - IQ scores vary from one test to another

4 - all IQ tests are culturally biased to a degree - the younger the student the less valid - reliable the test - IQ tests do not predict a person's ability to function in society (3) Reduce bias in intelligence tests because we have cultural over identified culturally different children as mildly retarded (assumed cultural familial etiology)

B. Adaptive behavior: Measured by observation and questionnaires filled out by parents and teachers

7. Educational Considerations A. Milder retardation greatest emphasis on functional academic skills as well as skills listed below

Moderate/Severe retardation greater emphasis self-help, community living and vocational skills

B. Systematic Instruction - Example of special education teacher intervention (1) instructional prompts "what do you need to do next?" (2) consequences for performance - positive reinforces: praise to tokens

5 (3) transfer of stimulus control phasing out instructional prompts C. Generally better to teach MR students daily living skills in the actual “real life” setting where they will be using them – facilitates generalization and transfer

8. Early childhood Programs A. Programs designed for prevention B. Programs designed for further development (California Search and Service)

9. Transition to adulthood A. Transition programming {school to work and community adjustment} should begin in the elementary years – with specific curriculum

B. Community Adjustment (1) living with family (2) community residential facility (CRF)/group homes (3) supportive living

C. Employment (1) when persons with MR are not successful on the

6 job, the cause more often involves behaviors related to job responsibility and social skills than to job task performance per se. (2) vocational training supports - sheltered workshop - supportive competitive employment (job coach) - competitive employment